Bottom hole assemblies can use a variety of tools downhole that are surface controlled through hydraulic control lines that run along a tubing string from the surface at one end to the downhole tool at the other end. Safety valves and isolation valve are just some examples. Frequently these lines are run in bundles with different termination points and into wellbores that are not necessarily vertical. These lines have to get past packers in some applications. Generally the lines are secured to the exterior of the tubing string as the joints are added at the surface. Since these lines go through close clearances such as a tubing string moving through a cased and cemented wellbore, there are opportunities for such lines to become damages in various ways. One of the worst ways that such damage can occur is that a hole develops in a control line. Depending on the size of the hole and the resulting ability of the control line to convey the required pressure to the downhole tool, the presence of a hole in a control line can result in the downhole tool being inoperative from the surface. When this happens the string has to be pulled so that the location of the damage can be determined and repaired. This causes significant downtime that can be very costly to the well operator.
In the past efforts were directed to protect control lines run into wellbores by encapsulating them or using other protective devices. A few representative examples are U.S. Pat. Nos. 4,262,703; 3,844,345; 3,806,168 and 3,780,802.
The present invention provides a method and associated equipment to locate the line break and straddle it while providing sealing on opposed ends of the break whereupon normal pressurized flow can be resumed by opening a passage through the device that straddled the break. The equipment may have limits to certain situations and may not be optimally suitable for other situations. One limiting condition may be a complete control line break or situations where the line is crimped or bent so badly as to impede movement of the repair device through it. However, options are available for unique situations. For example, the crimps in the line can be taken out with a tool that is pumped down the control line to the point of the hole in the wall and then retrieved so as to take the kinks out of the line to a sufficient extend that the repair device will travel to the hole location. Alternatively the repair device can be configured with a leading swage 50 shown in FIG. 6 to return the internal dimension of the control line to the original dimension as the repair device is advanced to the hole location.
In one aspect of the device, the wall hole is straddled with seals before and after and the seal that is uphole of hole energized to close leaving a straddle tube sealed on opposed ends that only needs communication through it to be opened up so that normal control line operations can resume.
In another option, a light source and camera can be first run into the control line to determine the hole location or locations as a preliminary indication of whether a repair is even feasible.
These and other details of the method and associated apparatus for repair of control or other types of lines in a downhole environment will be more readily understood by those skilled in the art from a review of the description of the preferred embodiment and the associated drawings while understanding that the full scope of the invention is to be found in the appended claims.